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Uncertainty In Environmental Decision-Making: Issues, Challenges And Future Directions, Holger R. Maier, James C. Ascough Ii Jul 2006

Uncertainty In Environmental Decision-Making: Issues, Challenges And Future Directions, Holger R. Maier, James C. Ascough Ii

International Congress on Environmental Modelling and Software

Environmental decision-making is complicated by the complexity of natural systems and the often competing needs of multiple stakeholders. Modelling tools are often used to assist at various stages of the environmental decision-making process. If such models are to provide effective decision support, the uncertainties associated with all aspects of the decision-making process need to be taken into account explicitly. However, as models become more complex in order to better represent integrated environmental, social and economic systems, achieving this goal becomes more difficult. Some of the important issues that need to be addressed in relation to the incorporation of uncertainty in …

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State-Parameter Estimation Of Ecosystem Models Using A Smoothed Ensemble Kalman Filter, M. Chen, Shuguang Liu, Larry L. Tieszen Jul 2006

State-Parameter Estimation Of Ecosystem Models Using A Smoothed Ensemble Kalman Filter, M. Chen, Shuguang Liu, Larry L. Tieszen

International Congress on Environmental Modelling and Software

Much of the effort in data assimilation methods for carbon dynamics analysis has focused on estimating optimal values for either model parameters or state variables. The main weakness of estimating parameter values alone (i.e., without considering state variables) is that all errors from input, output, and model structure are attributed to model parameter uncertainties. On the other hand, the accuracy of estimating state variables may be reduced if the temporal evolution of parameter values is not incorporated. This research develops a smoothed ensemble Kalman filter (SEnKF) to estimate simultaneously the system states and model parameters of an eddy flux partition …

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The Development Of A Farming Systems Model (Apsim) A Disciplined Approach., Dean Holzworth, Holger Meinke, Peter Devoil, Malcolm Wegener, Neil Huth, Graeme Hammer, Mark Howden, Michael Robertson, Peter Carberry, David Freebairn, Chris Murphy Jul 2006

The Development Of A Farming Systems Model (Apsim) A Disciplined Approach., Dean Holzworth, Holger Meinke, Peter Devoil, Malcolm Wegener, Neil Huth, Graeme Hammer, Mark Howden, Michael Robertson, Peter Carberry, David Freebairn, Chris Murphy

International Congress on Environmental Modelling and Software

The Agricultural Production Systems Simulator (APSIM) is a mature and stable modelling framework used widely in Australia in the domain of farming systems research and extension. It is capable of simulating a diverse range of farming systems including broad acre dryland and irrigated cropping, small holder farming, on-farm agroforestry systems including the interaction of trees and crops, and through collaboration with other groups, integrated stock and cropping enterprises. APSIM was developed primarily as a research tool to investigate on-farm management practices, natural resource issues including salinity and solute movement, climate risk studies looking at modifying farm practices and climate change …

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Resolving Model Parameter Values From C And N Stock Measurements In A Wide Range Of Tropical Mature Forests Using Nonlinear Inversion, Shuguang Liu, Pamela Anderson, Guoyi Zhou, Boone Kauffman, Flint Hughes, David Schimel, Vicente Watson, Joseph Tosi Jul 2006

Resolving Model Parameter Values From C And N Stock Measurements In A Wide Range Of Tropical Mature Forests Using Nonlinear Inversion, Shuguang Liu, Pamela Anderson, Guoyi Zhou, Boone Kauffman, Flint Hughes, David Schimel, Vicente Watson, Joseph Tosi

International Congress on Environmental Modelling and Software

Objectively assessing the performance of a model and deriving model parameter values from observations are critical and challenging in landscape to regional modeling. In this paper, we applied a nonlinear inversion technique to calibrate the ecosystem model CENTURY against carbon and nitrogen stock measurements collected from 33 mature tropical forest sites in seven life zones in Costa Rica. Net primary productivity from the MODIS, C and N stocks in aboveground live biomass, litter, coarse woody debris (CWD), and in soils were used to calibrate the model. To investigate the resolution of available observations on the number of adjustable parameters, inversion …

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Without A Common Mental Model A Dss Makes No Sense (A New Approach To Frame Analysis Using Mental Models), M. J. Kolkman, A. Van Der Veen Jul 2006

Without A Common Mental Model A Dss Makes No Sense (A New Approach To Frame Analysis Using Mental Models), M. J. Kolkman, A. Van Der Veen

International Congress on Environmental Modelling and Software

In order to understand why the use of model software and its results in decision making is surrounded with a diversity of problems, this paper presents a new theoretical framework. The framework is based on the notions of frame and mental model that are commonly used in social sciences and psychology. Mental models are found to guide the activities of knowledge producing scientists, DSS builders, decision makers and stakeholders. These activities are described in a modelling cycle and a decision making cycle. The model – both software and mental – functions as an intermediate for knowledge transfer. The theoretical framework, …

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Air Quality Modelling: State-Of-The-Art, R. San José, A. Baklanov, R. S. Sokhi, Kostas Karatzas, J. L. Pérez Jul 2006

Air Quality Modelling: State-Of-The-Art, R. San José, A. Baklanov, R. S. Sokhi, Kostas Karatzas, J. L. Pérez

International Congress on Environmental Modelling and Software

Air quality modeling is an area with a significant progress and interest during the last two decades. It covers all aspects related to pollution dispersion and impact on different ecosystems. It is very much related to the meteorological field since the atmosphere is governed by the general laws derived by the Navier-Stokes equation system. Progress in computer capabilities during the last decades has impulse substantially the research on air quality modeling in a parallel way. Air pollution modeling covers a very complex and interdisciplinary area where we include remote sensing – land use impact -, initial and boundary conditions, data …

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Watershed Health Assessment Tools-Investigating Fisheries (What-If): A Modeling Toolkit For Watershed And Fisheries Management., Brenda Rashleigh, Craig Barber, Mike Cyterski, John Johnston, Yusuf Mohamoud, Rajbir Parmar Jul 2006

Watershed Health Assessment Tools-Investigating Fisheries (What-If): A Modeling Toolkit For Watershed And Fisheries Management., Brenda Rashleigh, Craig Barber, Mike Cyterski, John Johnston, Yusuf Mohamoud, Rajbir Parmar

International Congress on Environmental Modelling and Software

The Watershed Health Assessment Tools-Investigating Fisheries (WHAT-IF) is a decision-analysis modeling toolkit for personal computers that supports watershed and fisheries management. The WHAT-IF toolkit includes a relational database, help-system functions and documentation, and multiple statistical and simulation modeling tools. The tools consist of a hydrologic and stream geometry calculator, a fish assemblage predictor, a fish habitat suitability calculator, and a process-based model to predict biomass dynamics of stream biota (the BASS model). The tools can be used to assess conditions and associated stressors in aquatic ecosystems, to examine causes of impairment, and to forecast ecological outcomes of habitat alterations and …

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Bayesian Decision Networks - Going Beyond Expert Elicitation For Parameterisation And Evaluation Of Ecological Endpoints., C. A. Pollino, Barry T. Hart Jul 2006

Bayesian Decision Networks - Going Beyond Expert Elicitation For Parameterisation And Evaluation Of Ecological Endpoints., C. A. Pollino, Barry T. Hart

International Congress on Environmental Modelling and Software

Ecological and integrative analyses routinely involve the synthesis of a range of information sources into a single model. Bayesian decision networks (BDN) are increasingly being used for this purpose because they are flexible, transparent and relatively easy to use. Indeed, BDNs offer a scientific and pragmatic approach to improve decision-making in environmental management, directly addressing management needs, while promoting stakeholder participatory processes. However, despite their advantages, many BDNs developed to meet such needs are not being developed or applied to their full potential. The majority of BDNs published to date rely only on expert opinion to parameterise and evaluate ecologically …

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Utilizing Artificial Neural Networks To Backtrack Source Location, Zhiqiang Li, Donna M. Rizzo, Nancy Hayden Jul 2006

Utilizing Artificial Neural Networks To Backtrack Source Location, Zhiqiang Li, Donna M. Rizzo, Nancy Hayden

International Congress on Environmental Modelling and Software

Determining the location of the contaminant source is important for improving remediation and site management decisions at many contaminated groundwater sites. At large sites, numerical flow and transport models have been developed that use historical measurement data for calibration. A well-calibrated model is useful for predicting plume migration and other management purposes; however, it is difficult to back out the source with these forward flow and transport models. We present a novel technique utilizing Artificial Neural Networks (ANNs) to backtrack source location and earlier plume concentrations from recent plume information. For proof-of-concept, two tracer tests (a non-point-source and a point-source) …

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A 3d Hydrodynamic Lake Model: Simulation On Great Slave Lake, Luis F. León, David C. L. Lam, William Schertzer, David Swayne Jul 2006

A 3d Hydrodynamic Lake Model: Simulation On Great Slave Lake, Luis F. León, David C. L. Lam, William Schertzer, David Swayne

International Congress on Environmental Modelling and Software

Large lakes are recognized as an important influence on the circulation of the atmosphere; in return the resulting meteorological forcing also affects the lake thermal structure. This interaction is complex and continues to be a critical issue considering the millions of lakes in Canada, many of which are large, and are unaccounted for in the current climatic models. This paper evaluates the predictive capability of the 3-D Estuary and Lake COmputer Model (ELCOM) using relatively high quality data collected on Great Slave Lake - one of the largest lakes of the world in Canada’s northern climatic system. This assessment is …

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Avoiding The Finite Difference Sensitivity Analysis Deathtrap By Using The Complex-Step Derivative Approximation Technique, Dirk J. W. De Pauw, Peter A. Vanrolleghem Jul 2006

Avoiding The Finite Difference Sensitivity Analysis Deathtrap By Using The Complex-Step Derivative Approximation Technique, Dirk J. W. De Pauw, Peter A. Vanrolleghem

International Congress on Environmental Modelling and Software

In this paper, the complex-step derivative approximation technique will be used for calculating local sensitivity functions. This technique is compared to the finite difference approximation, probably the most used local sensitivity analysis technique. For this comparison, 4 biotechnological models with varying model complexity were used. A well known problem of the finite difference approximation is the choice of a suitable perturbation factor in order to avoid non-linear model effects or numerical errors due to the subtraction of almost equal numbers. The main advantage of the complex-step derivative approximation technique is that it is not susceptible to errors introduced by small …

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Rank-Equivalence Method For Sensitivity Analysis Of An Integrated Model Of A River Catchment, J. K. Ravalico, Graeme C. Dandy, Holger R. Maier Jul 2006

Rank-Equivalence Method For Sensitivity Analysis Of An Integrated Model Of A River Catchment, J. K. Ravalico, Graeme C. Dandy, Holger R. Maier

International Congress on Environmental Modelling and Software

Integrated Assessment Modelling (IAM) incorporates knowledge from different disciplines to provide an overarching assessment of the impact of different management decisions. Integrated models generally require numerous parameters from varying sources, many not known with certainty. Rapid increases in model size and complexity, particularly in the case of integrated models for decision-making, pose new challenges for effective sensitivity analysis. Some of the identified shortcomings of existing sensitivity analysis methods in the context of IAM include: computational inefficiency, failure to assess parameter interactions, excessive data requirements (e.g. requiring parameter probability distributions), assumptions of model linearity and monotonicity and, in particular, difficulty of …

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Multi-Scale Analysis And Modelling Of Natural Resource Management Options, Frank Ewert, Herman Van Keulen, Martin Van Ittersum, Ken Giller, Peter Leffelaar Jul 2006

Multi-Scale Analysis And Modelling Of Natural Resource Management Options, Frank Ewert, Herman Van Keulen, Martin Van Ittersum, Ken Giller, Peter Leffelaar

International Congress on Environmental Modelling and Software

Problems related to natural resource management (NRM) are typically complex and require integration of information across several scales and disciplines. Operational concepts to support such integration are scarce. Systems analysis and modelling can be helpful but the complexity of environmental systems also requires application of appropriate upscaling methods. Simultaneous assessment and modelling of system behaviour at several levels of organisation poses particular problems. Here, we provide an introductory overview on the critical issues related to multi-scale analysis and modelling of NRM. We describe the problems related to NRM within the context of systems thinking and hierarchy theory. Methods of upscaling …

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Multi-Scale Analysis And Modelling Of Natural Resource Management Options, Frank Ewert, Herman Van Keulen, Martin Van Ittersum, Ken Giller, Peter Leffelaar Jul 2006

Multi-Scale Analysis And Modelling Of Natural Resource Management Options, Frank Ewert, Herman Van Keulen, Martin Van Ittersum, Ken Giller, Peter Leffelaar

International Congress on Environmental Modelling and Software

Problems related to natural resource management (NRM) are typically complex and require integration of information across several scales and disciplines. Operational concepts to support such integration are scarce. Systems analysis and modelling can be helpful but the complexity of environmental systems also requires application of appropriate upscaling methods. Simultaneous assessment and modelling of system behaviour at several levels of organisation poses particular problems. Here, we provide an introductory overview on the critical issues related to multi-scale analysis and modelling of NRM. We describe the problems related to NRM within the context of systems thinking and hierarchy theory. Methods of upscaling …

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Upscaling Terrestrial Carbon Dynamics From Sites To Regions With Uncertainty Measures: The Gems Experience, Shuguang Liu, Z. Li, Jinxun Liu, Thomas R. Loveland, M. Chen, Larry L. Tieszen Jul 2006

Upscaling Terrestrial Carbon Dynamics From Sites To Regions With Uncertainty Measures: The Gems Experience, Shuguang Liu, Z. Li, Jinxun Liu, Thomas R. Loveland, M. Chen, Larry L. Tieszen

International Congress on Environmental Modelling and Software

Upscaling the spatial and temporal changes of carbon stocks and fluxes from sites to regions is challenging owing to the spatial and temporal variances and covariance of driving variables and the uncertainties in both the model and the input data. Although various modeling approaches have been developed to facilitate the upscaling process, few deal with error transfer from model input to output, and error propagation in time and space. We develop the General Ensemble Biogeochemical Modeling System (GEMS) for upscaling carbon stocks and fluxes from sites to regions with measures of uncertainty. GEMS relies on site-scale biogeochemical models (e.g., the …

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Intelligent Configuration Of Numerical Solvers Of Environmental Ode/Dae Models Using Machine Learning Techniques, Petra Claeys, Peter A. Vanrolleghem Jul 2006

Intelligent Configuration Of Numerical Solvers Of Environmental Ode/Dae Models Using Machine Learning Techniques, Petra Claeys, Peter A. Vanrolleghem

International Congress on Environmental Modelling and Software

The models considered in this work contain combinations of a large number of non-linear differential equations and algebraic equations, which have to be solved numerically. Because of this, running simulation experiments on a computer can be very time-consuming, i.e. it can last for days or even weeks. On top of that, some solvers are not appropriate for solving certain of these systems. For example, stiff solvers are only appropriate for stiff systems while they are not the best choice for non-stiff systems. Choosing the appropriate solver and solver settings for a certain initialized model can significantly shorten the computation time. …

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Tornado: A Versatile And Efficient Modelling And Virtual Experimentation Kernel For Water Quality Systems, Filip Claeys, Dirk J. W. De Pauw, Lorenzo Benedetti, Ingmar Nopens, Peter A. Vanrolleghem Jul 2006

Tornado: A Versatile And Efficient Modelling And Virtual Experimentation Kernel For Water Quality Systems, Filip Claeys, Dirk J. W. De Pauw, Lorenzo Benedetti, Ingmar Nopens, Peter A. Vanrolleghem

International Congress on Environmental Modelling and Software

Recently, a new kernel for modelling and virtual experimentation (i.e. any evaluation of a model) in the domain of water quality management was developed. This kernel was named “Tornado” and will be included in the new generation of the WEST product family, as well as in several other products (e.g. DHI’s MOUSE-TRAP) and projects. Most important issues during development were versatility and efficiency. This paper focuses mainly on the rationale for the new development, and the major features of the resulting kernel. It is argued that classical approaches (such as the adoption of MATLAB/SIMULINK, custom FORTRAN codes and/or domain-specific simulators) …

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Landscape Design And Agricultural Land-Use Allocation Using Pareto-Based Multi-Objective Differential Evolution, Jeroen C. J. Groot, Walter A. H. Rossing, André Jellema, Martin Van Ittersum Jul 2006

Landscape Design And Agricultural Land-Use Allocation Using Pareto-Based Multi-Objective Differential Evolution, Jeroen C. J. Groot, Walter A. H. Rossing, André Jellema, Martin Van Ittersum

International Congress on Environmental Modelling and Software

Intensively managed agricultural areas in North-Western Europe are undergoing a shift from solely production oriented use to provision of multiple services and functions. Design of multifunctional agricultural landscapes can be supported by exploration of the potential to effectively combine economic performance, landscape identity, nature conservation and environmental quality. The Landscape IMAGES methodology enables spatially explicit exploration of options by multi-objective optimization, for multifunctional agriculture in landscapes at a scale of a few km². The framework has been developed to support stakeholder discussions and informed decision making. For simultaneous optimization of multiple objectives the evolutionary algorithm of Differential Evolution is employed. …

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Experience Gained From The Use Of Environmental Information Systems For The Public In The State Of Baden-Wuerttemberg, Werner Geiger, C. Düpmeier, M. Ruchter, T. Schlachter, R. Ebel, M. Linnenbach Jul 2006

Experience Gained From The Use Of Environmental Information Systems For The Public In The State Of Baden-Wuerttemberg, Werner Geiger, C. Düpmeier, M. Ruchter, T. Schlachter, R. Ebel, M. Linnenbach

International Congress on Environmental Modelling and Software

For the protection of the natural environment and a sustainable development, joint responsibility and participation of the citizens are indispensable. In this connection, enlightenment and information of the public and the promotion of environmental awareness play a crucial role. This contribution shall present various environmental information systems for the public and report about the experience gained from their development and operation. The systems have been developed as parts of the Baden-Wuerttemberg Environmental Information System by Forschungszentrum Karlsruhe in cooperation with the State Institute for the Environment, Measurements, and Nature Protection. In particular, the Baden-Wuerttemberg Environmental Information Network with a portal …

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Building A Community Modeling And Information Sharing Culture, Alexey Voinov, Raleigh R. Hood, John D. Daues Jul 2006

Building A Community Modeling And Information Sharing Culture, Alexey Voinov, Raleigh R. Hood, John D. Daues

International Congress on Environmental Modelling and Software

By copying information from sources and distributing it to new destinations we do not loseinformation at the sources. Nevertheless, exchange of information is still restricted by patent law, as well asby institutional, cultural and traditional hurdles that create protective barriers hindering the free flow of thisvaluable commodity. We believe that one of the greatest challenges we face in creating a new researchparadigm will be building the community modeling and information sharing culture. How do we getengineers and scientists to put aside their traditional modes of doing business? How do we provide theincentives that will be required to make these changes …

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Uncertainty Analysis Associated With Rainfall Spatial Distribution In An Experimental Semiarid Watershed, Northeastern Brazil, Lúcio Flávio Ferreira Moreira, A. M. Righetto, V. M. De A. Medeiros Jul 2006

Uncertainty Analysis Associated With Rainfall Spatial Distribution In An Experimental Semiarid Watershed, Northeastern Brazil, Lúcio Flávio Ferreira Moreira, A. M. Righetto, V. M. De A. Medeiros

International Congress on Environmental Modelling and Software

In this paper the main goal was to analyze the effect of spatial variability of rainfall on runoff in an experimental monitored watershed (2.108 km2) located on a semiarid region (Seridó Potiguar), Rio Grande do Norte-Brazil. To accomplish this, a rainfall-runoff-sediment hydrologic model was used. The study area was divided into 143 elements (planes and channels). Rainfall spatial distribution, estimated using the inverse of distance method, was used as input to calculate rainfall spatial variability index for three observed storm events and different combinations of recording gauge arrangements. This index was considered in this study as an indicator used to …

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Modelling Of Water Pollution In Urban Areas With Gis And Multivariate Statistical Methods, L. Matejicek Jul 2006

Modelling Of Water Pollution In Urban Areas With Gis And Multivariate Statistical Methods, L. Matejicek

International Congress on Environmental Modelling and Software

Integrating modelling of water pollution and GIS enables the connection of environmental process models with geospatial data describing the physical environment. Time series of water pollution data at monitoring profiles are used to complement the spatial database and to interpret the results of data analysis. In this case, the multivariate statistical methods provide an exploratory environment for data analysis and an indication of seasonal changes in the framework of surface water pollution. In addition to a wide range of useful multivariate methods, principal component analysis (PCA) and factor analysis (FA) are used to differentiate seasonal water pollution at monitoring profiles. …

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Future Solutions: Integrated Models For Sea And Other Land-Use Decision-Making., Ruth Waldick, David Brunckhorst, Ian Campbelld, Jeff Carmichael Jul 2006

Future Solutions: Integrated Models For Sea And Other Land-Use Decision-Making., Ruth Waldick, David Brunckhorst, Ian Campbelld, Jeff Carmichael

International Congress on Environmental Modelling and Software

Since policies should reflect societal values and aspirations, decision-making would benefit from tools that allow consideration of all entities that contribute to, or are affected by decisions. At a minimum, policy should include those key economic, social, and environmental activities taking place within a geophysically relevant area. The barriers that impede the development of integrated modeling programs that try to include many of the processes and outcomes of interest in studying a problem represent a series of common challenges associated with most integrative and cross-jurisdictional projects. Although computer-based modeling and scenario tools can inform the decision-making process, the scope of …

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Modelling Farmer Decision Making For Natural Resource Management Outcomes, Brett A. Bryan, J. Ward, Neville D. Crossman Jul 2006

Modelling Farmer Decision Making For Natural Resource Management Outcomes, Brett A. Bryan, J. Ward, Neville D. Crossman

International Congress on Environmental Modelling and Software

This paper presents a conceptual modelling and simulation methodology that incorporates dryland farmer decision making into regional- and landscape-level natural resource management (NRM) planning. Decision making for many NRM on ground actions is made at the farm level so it makes sense to incorporate farmer behaviour into regional planning for meeting regional environmental objectives. Our model applies multi-attribute farmer utility functions within an agent-based simulation environment to model temporal change in land use and landscapes resulting from farmer implementation of on ground NRM actions. Farmer decision profiles are characterized using a survey of over 500 farmers. Landscape futures can also …

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Tools To Support A Model-Based Methodology For Benefit/Cost/Risk Analysis Of Wastewater Treatment Systems, Lorenzo Benedetti, Davide Bixio, Filip Claeys, Peter A. Vanrolleghem Jul 2006

Tools To Support A Model-Based Methodology For Benefit/Cost/Risk Analysis Of Wastewater Treatment Systems, Lorenzo Benedetti, Davide Bixio, Filip Claeys, Peter A. Vanrolleghem

International Congress on Environmental Modelling and Software

This paper presents a set of tools developed to support an innovative four-step methodology to design and upgrade wastewater treatment systems. For the first step of data collection and data reconstruction, two different tools have been developed, one for situations where data are available (using data reconstruction methods) and another for situations where no data are (yet) available (based on a simple draining catchment model driven by actual local rain series). The second step, i.e. model building, implied the development of a new simulation platform and of grid software to deal with the considerable simulation load generated by the third …

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Mike Basin, David Wood Jul 2006

Mike Basin, David Wood

International Congress on Environmental Modelling and Software

MIKE BASIN addresses water allocation, conjunctive use, reservoir operation, or water quality issues. It couples ArcGIS with hydrologic modeling to provide basin-scale solutions. The MIKE BASIN philosophy is to keep modeling simple and intuitive, yet provide in-depth insight for planning and management. In MIKE BASIN, the emphasis is on both simulation and visualization in both space and time, making it appropriate for building understanding and consensus. MIKE BASIN is a quasi-steady-state mass balance model, allowing for routed river flows. The water quality solution assumes purely advective transport. Decay during transport can be modeled. The groundwater description uses the linear reservoir …

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Ribasim River Basin Planning And Management Simulation Program, Delft Hydraulics Jul 2006

Ribasim River Basin Planning And Management Simulation Program, Delft Hydraulics

International Congress on Environmental Modelling and Software

RIBASIM (River Basin Simulation Model) is a generic model package for analyzing the behaviour of river basins under various hydrological conditions. The model package is a comprehensive and flexible tool which links the hydrological water inputs at various locations with the specific water-users in the basin. RIBASIM is designed for river basin planning and management RIBASIM follows a structured approach to river basin planning and management. RIBASIM enables the user to evaluate a variety of measures related to infrastructure, operational and demand management and the results in terms of water quantity and water quality. RIBASIM generates water distribution patterns and …

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Assessment Of Ecological State Of Surface Waters In Arrow Project: Robust Multivariate Predictive Models, J. Ráček, Jiri Jarkovsky, Danka Nemethova, P. Brabec Jul 2006

Assessment Of Ecological State Of Surface Waters In Arrow Project: Robust Multivariate Predictive Models, J. Ráček, Jiri Jarkovsky, Danka Nemethova, P. Brabec

International Congress on Environmental Modelling and Software

The ARROW (www.cba.muni.cz/arrow/eng - Assessment and Reference Reports of Water monitoring) project is the project of implementation of EU Water Framework Directive in the monitoring of surface waters of the Czech Republic and covers all aspects of this problem from data sampling to informatics solution (focusing on the ecostat). The project is based on long term development of this field in the Czech Republic and it is carried out under the supervision of the Ministry of the Environment of the CR. The important part of the ARROW project is the development and implementation of a Czech approach to the evaluation …

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Data Mining And Image Segmentation Approaches For Classifying Defoliation In Aerial Forest Imagery, K. Fukuda, P. A. Pearson Jul 2006

Data Mining And Image Segmentation Approaches For Classifying Defoliation In Aerial Forest Imagery, K. Fukuda, P. A. Pearson

International Congress on Environmental Modelling and Software

Experimental data mining and image segmentation approaches are developed to add insight towards aerial image interpretation for defoliation survey procedures. A decision tree classifier generated with a data mining package, WEKA [Witten and Frank, 2005], based on the contents of a small number of training data points, identified from known classes, is used to predict the extents of regions containing different levels of tree mortality (severe, moderate, light and non attack) and land cover (vegetation and ground surface). This approach is applicable to low quality imagery without traditional image pre-processing (e.g., normalization or noise reduction). To generate the decision tree, …

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Comparison Of Linear And Non-Linear Pls Methods For Soft-Sensing Of An Sbr For Nutrient Removal, K. Villez, D. S. Lee, C. Rosen, Peter A. Vanrolleghem Jul 2006

Comparison Of Linear And Non-Linear Pls Methods For Soft-Sensing Of An Sbr For Nutrient Removal, K. Villez, D. S. Lee, C. Rosen, Peter A. Vanrolleghem

International Congress on Environmental Modelling and Software

Despite of promising results in research, advanced control strategies fail to gain trust in wastewater treatment practice. Due to the sensitivity of the biological processes to disturbances, operators are often unable to find the causes of faults due to the lack of effective real-time on-line monitoring. Strategies for on-line monitoring are therefore essential to enhance biological process control. Therefore, a suitable multivariate soft-sensor is desired for fault detection and control for a pilot-scale sequencing batch reactor (SBR) system to allow effluent quality to be estimated well before off-line analysis is finished. For this purpose, several multivariate methods are available, including …

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